Karunaratne's career-best was the mainstay of Sri Lanka's score, while fifties from their five, six and seven of Dinesh Chandimal, Niroshan Dickwella and Dilruwan Perera boosted the tally beyond 450.
Having won the opening match on a dramatic final day to stop an abysmal run of form across all formats, Sri Lanka played with renewed confidence on Friday to post 254-3 after winning the toss.
The listless efforts of two premier left-arm pacers summed up Pakistan's fortunes not only in the Dubai Test but the two-match series.More news: Under fire, Trump blames Puerto Ricans for slow hurricane response
"The Champions Trophy team has been retained except Azhar Ali, who has been rested for the ODI series to gain full fitness, said Pakistan Cricket Board (PCB) chief selector Inzamam ul Haq". He defused Yasir Shah judiciously again, routinely getting inside the line of the ball to work him towards square leg. He returned to the dressing room for treatment after bowling just three deliveries of his 17th over.
Amir picked up a stress-related injury of his right shin and has been advised rest for the next two to three weeks.
The pink-ball Test, the sixth in all since Australia and New Zealand played the first such game in Adelaide in 2015, will also be a new experience for the Sri Lankan.
Karunaratne plays a shot during the second day. Attempting to deliver the fifth ball of his 19th over, Wahab aborted his run up five times, failing, inexplicably, to get into his usual delivery slide.More news: Say goodbye to East vs. West; NBA alters All-Star Game format
These all are some terms of the Pakistan vs Sri Lanka match which is maintain its stranglehold.
Rangana Herath managed to score an unbeaten 27 as Sri Lanka were bowled out for 482.
Masood had a stroke of luck when he was given not out and Chandimal chose not to review after Dilruwan struck the opener in front, replays showing he should have been given, and Aslam ought to have been run out following a mix-up but Pakistan got through to stumps without losing a wicket.
It was 21 runs short of the follow-on mark but Sri Lanka did not enforce it.More news: Here's where you can score some free tacos Wednesday!